In an inkjet recording apparatus, a so-called shear mode type inkjet head is proposed in which an ink droplet is ejected from a nozzle hole by using shear mode deformation of a piezoelectric member.
The inkjet head includes a base substrate in which plural groove parts are formed into ink chambers. A nozzle plate including nozzle holes facing the respective groove parts of the base substrate is bonded to the end face of the base substrate. An electrode to apply power to the piezoelectric member is formed on the inner wall surface of the ink chamber which the nozzle hole faces. An organic protection film against ink, in which a poly-chloro-para-xylylene film and a poly-para-xylylene film are laminated in this order, is formed on the surface of the electrode.
As stated above, since the poly-chloro-para-xylylene film is formed as a smooth ground film for the poly-para-xylylene film which is apt to form a pin hole by influence of roughness of a ground, the poly-para-xylylene film having no pin hole and having high reliability is formed.
After the nozzle plate is bonded to the base substrate, when a nozzle is formed in the nozzle plate by laser beam, the nozzle hole is formed into a truncated cone shape. At that time, the protection film on the inner wall surface of the ink chamber may be exposed to the laser beam, and the protection film may be damaged. Thus, when liquid having electrical conductivity is used as ink, there is a fear that the print quality of the inkjet head and the durability can not be maintained.